1. Field of the Invention
The subject invention pertains to the hazards of hydrogen sulfide and more specifically to a system for responding to an excessive amount of hydrogen sulfide at a well site.
2. Description of Related Art
Hydrogen sulfide, H2S, is a toxic gas that often accompanies the production of gas, oil and water. H2S can usually be contained, but if it escapes, an H2S monitor can be used for alerting personnel in the area. In response to sensing about 10 to 20 ppm of H2S, typical H2S monitors will sound an alarm that warns of the danger. Once the alarm sounds, personnel often have sufficient time to vacate the area. In some cases, however, someone or everyone in the area may be overcome by the gas and fall to the ground. Since H2S is heavier than air, an unconscious person lying on the ground may continue breathing the toxic gas. If outside help is not quickly summoned to the area, eventually those continuing to breath the gas may die.
U.S. Pat. No. 6,252,510 discloses an H2S system that calls for outside help upon sensing an excessive amount of H2S at a distant location. The system appears to be designed for an established chemical plant where the H2S monitor is at a fixed, known location. Such a system may be fine for such an application because the location of the H2S monitor is known, thus the location where medical assistance is needed is also known.
However, in the case of an oilfield crew working among numerous remote oilfields, the location of the crew may be unknown to those that may otherwise be able to dispatch help to where it is needed. Thus, oilfield workers may be left stranded in an emergency and have to rely solely on their own ability to help themselves.
It is conceivable to install a dedicated H2S monitor at each and every oilfield; however, such an approach would be unnecessarily expensive because the vast majority of oilfields operate unattended. Often, an H2S monitor and an emergency call-out alarm is only needed when a work crew or other personnel are in the area.
Consequently, a need exists for an H2S monitor that can not only travel with a work crew but also communicate to outside help the location of the monitor.